Low CO2 with high performance is affordable and available

Lotus Engineering, the automotive consultancy
division of Lotus, and Continental Division Powertrain have presented the results of their “Low
CO2”
research collaboration. The Low CO2 vehicle concept is being proposed as a practical
option for manufacturers to reduce their fleet average CO2
emissions.

The Low CO2
vehicle concept is
demonstrated in an Opel Astra and uses a Lotus Engineeringdesigned pressure-charged three-cylinder 1.5-litre gasoline
engine integrated with a number of Lotus and Continental technologies. It features an
innovative integrated exhaust manifold design, centrally-mounted injectors, cam profile
switching for lift and timing, a high pressure fuel pump, and a mild hybrid drive. The Low CO2
Astra produces a g/km CO2
reduction of 15% against the naturally aspirated 1.8 litre 4 cylinder
engine version of the same vehicle. While forging comparisons to the most frugal B-segment
cars, the Low CO2 Astra – on the NEDC (New European Driving Cycle) – produces performance
figures that are comparable to market leading C-segment cars with larger engines.

Comparison Table

The primary objective of the Low CO2 project was to deliver
greatly reduced CO2 emissions while maintaining an engaging driving
experience from an affordable set of technologies. The solution
employs a cleverly integrated set of powertrain systems within a
downsized overall package.

The collaboration concluded in early February with the completion
of extensive dynamometer and road testing at Continental’s facility
in Toulouse, France and Lotus Engineering’s Hethel Headquarters in
the UK. The programme was grant-aided through the UK’s Energy Saving
Trust’s Low Carbon R&D Programme funded by the UK Government’s
Department for Transport.

Mike Kimberley, Chief Executive Officer of Group Lotus plc, said:
“Through intelligent integration of a range of proven and newly
available technologies, we have delivered a car that engages and
excites the keen motorist with the superb power and torque figures
and crucially has a lower impact on the environment. The most
important part of this project is that the solution is a combination
of technologies that are available and can be implemented in next
generation models and with further work beyond the scope of this
initial project, dramatic reductions in CO2 can theoretically be
achieved.

He continued: “I am very pleased with what has been achieved in
this project. Lotus Engineering is leading the industry across a
number of advanced green powertrain technologies, including electric
vehicles, hybrids, bio-fuels and developing more efficient gasoline
and diesel engines. We believe a crucial factor in the adoption of
green cars in the future will be ensuring they remain fun to drive.
This Low CO2 collaboration with Continental Division Powertrain
proves that objective has been reached.”

Dr. Hans Nuglisch, Senior Manager of this Low CO2 project at
Continental Division Powertrain, said: “The cooperation with our
partner, Lotus Engineering, has shown once again, that there is
still an enormous potential for additional innovation within the
internal combustion engine. Obviously electronics and mechatronics
are making vehicles more economical without compromising driving fun.
Additionally turbo charging combined with direct injection means
noticeably better fuel economy and lower CO2 emissions for the
gasoline engine. With our advanced expertise in low CO2 know how, we
provide clear benefits for our customers and will further strengthen
and improve our role as systems integration experts."

Transport Minister Jim Fitzpatrick said, "I am determined that
transport should play its part in tackling climate change, so it is
essential that our strategy focuses on driving forward new
technologies to make engines greener. This engine is one of the more
environmentally-friendly petrol engines around, raising the standard
for others to meet. I am pleased the Government was able to support
this project through the Low Carbon Research and Development
programme and look forward to the day when this type of technology
becomes commonplace on our roads" "With over 20% of the UK's total
carbon emissions produced by road transport every year,
technological advances in this area are vital,” explains Philip
Sellwood, Chief Executive of the Energy Saving Trust, which is
managing the initiative. “This project is an exciting opportunity
for innovative technologies to be developed and showcased."

Lotus brought to the project its world-class powertrain design,
development, testing and validation capabilities, with specific
expertise in engine downsizing and systems integration. Continental
Division Powertrain supplied its extensive experience in powertrain
management and control systems, especially in the areas of direct
fuel injection systems, hybrid drives, energy management, emission
after-treatment and a number of new technologies.

Technical details

Technical specification of the Low CO2 engine when installed in
Opel Astra:

Cylinders: 3

Displacement: 1.5 litres

Bore: 88mm

Stroke: 82mm

Compression ratio: 10.2:1

Fuel pump pressure: 200bar

Emissions (NEDC): 149 g/km CO2 meeting Euro 5 Emission
standards

Max power: 160ps @ 5000rpm

Max torque: 240Nm @ 2500rpm - 4000rpm

Mild hybrid motor output: 12kW

Mild hybrid energy storage system: 60v supercapacitors

Key features of the Low CO2 engine in detail:

CPS switching tappets:

Lotus Engineering’s Cam Profile Switching system incorporates
lobed tappets that vary valve lift and timing. The system is
produced under licence by INA and features in Porsche products in
its ‘VarioCam Plus’ system.

Continental Division Powertrain's electric water and fuel pumps
could save up to 2% of fuel.

Mild Hybrid Drive:

The Continental Division Powertrain system features unique water
cooled motor housing to match transmission to engine block.

Integrated Exhaust Manifold:

Lotus Engineering designed and developed a new advanced cylinder
head design featuring an integrated exhaust manifold. The
production-ready technology can significantly reduce manufacturing
costs, emissions and weight on most gasoline-engined passenger
vehicles. An integrated exhaust manifold has potential to:

Weight reduction: total system mass reduction of 20%
resulting from elimination of separate exhaust manifold

Improved engine durability

HOTFIRE

The Low CO2 project exploits the findings of the HOTFIRE project,
a previous research programme led by Lotus Engineering and also
including Siemens VDO, Loughborough University and University
College London. HOTFIRE, which started in October 2004, was based at
Loughborough University to explore a permanent homogeneous charge
direct injection strategy through the use of centrally-mounted
injectors.